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Find needle in Array Stack

Somewhere I saw script that compares two arrays and I must tell you it worked beautifully… What a time saver!!! The big boss comes to me (as I’ve become his go-to-guy when he needs something done quick) and asks if I could create an email distribution list which contains 1000 users. I said "no problem" do you have the list of users? He presented me the list and told me it is of the utmost importance that everyone on this list receives an email that will be distributed at the end of the week. Again we say, "NO Problem!!!" This list was in excel format and contained columns for Last name, First name, and email address. Since I required a property that would be unique to each user, I extracted the email addresses to a text file calledDistEmails.txt. My first step was to write a script that would locate each user in Active Directory and add them as a member to the Distribution list.

Example 

# Search AD using email addresses to get Disgtinguished Name (DN)
$ColEmail = Get-Content "C:\MyScripts\DistEmails.txt"
$Search = New-Object DirectoryServices.DirectorySearcher([ADSI]"")
foreach ($objEmail in $ColEmail){
$Search.Filter="(&(objectClass=User)(proxyAddresses=smtp:$objEmail))"
$objUsers = $Search.FindAll()
foreach ($objUser in $objUsers){$ADPath = $objUser.Path.Remove(0,7)}
foreach($Item in $ADPath)
{
$Mgroup=[ADSI]"LDAP://CN=CustName,DC=Domain,DC=Com"
$Mgroup.Member.add($Item)
$Mgroup.setinfo()
}
}

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Step One

The code above takes my list of email addresses, uses an LDAP filter to get the DN of each user, then adds each user to the Distribution Group. So here is when the fun began, remember what the boss said? Of utmostimportance that each person receives the email. First, I verified that the list did have 1000 user entries in it (counted excel spread sheet rows). Second, I needed to verify that there are 1000 members in the Distribution Group. How did I do this??? Wrote a script of course…

Example 

$Search = New-Object DirectoryServices.DirectorySearcher([ADSI]"")
$Search.Filter="(memberOf=CN=CustName,DC=Domain,DC=com)"
$objUsers = $Search.FindAll()
$ObjUsers.Count

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Code uses an LDAP filter to search for members of the Distribution Group, saves the results to the $objUsers array, then I just use the count property for the number of entries in the array. Note: the array count starts with 0 not 1. If my count property would have came out to 999 then I would have been home free, nothing is easy as my count was 989. Oh boy! How to I find Ten needles in a hay stack of 1000 users? Any thought of doing this manually by referencing the excel file and ‘Active Directory Users and Computers’ is out-of-the-question. I remembered posting one of Ying Li scripts in the script library that should do the trick. All I needed where two files to do a comparison on. One file I already had which was the DistEmails.txt file I used in the script to add group membership. The second file had to be a list of the email addresses of the current 990 members of the Distribution list. Time for some more code…

Example 

        $Search = New-Object DirectoryServices.DirectorySearcher([ADSI]"")
$Search.Filter="(memberOf=CN=CustName,DC=Domain,DC=com)"
$objUsers = $Search.FindAll()
foreach ($objUser in $objUsers){$colProps = $objUser.Properties
foreach($objProp in $colProps){$Items = $objProp.proxyaddresses}
$Items >> C:\MyScipts\GroupEmail.txt
}

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Now I have a text file Called GroupEmail.txt. The next step I had to do with the file was open it in WordPad and use "replace" to remove the "SMTP:" portion of the email address so that the entries match the addresses in the DistEmail.txt file. Time to compare the files to see which email addresses are missing

Example 

$arrFirst = Get-Content "C:\MyScripts\DistEmails.txt"
$arrSecond = Get-Content "C:\MyScripts\GroupEmail.txt"
New-Item "C:\MyScripts\FirstInSecond.txt" -Type file
New-Item "C:\MyScripts\FirstNOTinSecond.txt" -type file
foreach($First in $arrFirst){
if($arrSecond -contains $First)
{Add-Content "C:\MyScripts\FirstInSecond.txt" $First}
else
{Add-Content "C:\MyScripts\FirstNOTinSecond.txt" $First}
}

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Each file is placed in an array. We then create two new text files. We compare the two arrays and depending on the result we write the array entry in either the FirstInSecond.txt or the FirstNOTinSecond.txt file. Opening the FirstNOTinSecond.txt yields the results of our ten missing email addresses. Investigating the issue I found that the user accounts were still valid, just their email address had changed format. I added the missing ten users to the distribution group (yes, I did it manually via ADUC) and provided the boss with a list of users that are members of the group, all 1000 of them…

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